Northland’s buried treasure

‘Gold fever’ struck northern New Zealand in the late 1800s, and peaked at the turn of this century with 20,000 fortune-hunters spread across some 800,000 acres of land. What they were seeking was not metallic gold, but kauri gum: a rich golden resin which polishes up like glass and is one of this country’s most beautiful natural products.

All conifers produce resins, but kauri is one of the most prodigious bleeders. These mammoth trees, which can live for a thousand years or more. produce resin in response to injury or attack by other organisms. Over time, the trickles of resin seeping out of the tree can form huge lumps of solidified gum, some of which have weighed as much as 250 kilograms.

Kauri gum should have another name. Not a sturdy, lumpy word like gum, but something signifying liquid gold. A word that might imply mysterious landscapes and the hopes and dreams of genera­tions, as well as encompassing the beautiful and rare.

Quite apart from any poetic defi­ciencies in the name, strictly speak­ing, the stuff is not gum at all. It is a resin exuded by the fabled New Zea­land conifer Agathis australis in re­sponse to injury. The guardian of the tree, resin washes out and entraps boring insects, seals over the ravages of wind, lightning and animal dam­age, and prevents the entry of bacte­ria and fungi that may cause disease.

Gums, on the other hand, are sub­stances that swell in water to form gels or sticky solutions. Some are plant derived, like gum arabic from Acacia or the algae agar and carageen. Others are synthesised.

The kauri is a prodigious bleeder. Over the thousands of years of life of the largest of these leviathans the resin runs down the tree, collecting in the forks where it becomes crutch gum, pouring from the roots as sugar gum, or accumulating in frozen drips and long wax-like stalactites on the bark as candle gum. Over the aeons, layers of forest debris cover the gum to depths of up to 100 metres.

Stories tell of yields of two hun­dredweight of crutch gum from one tree, and of massive subterranean deposits of over 600lbs in a single nugget.

A lone gumdigger scrapes the oxidised rind from the gum he has collected by resting the lump on a stake and using a jack knife to clean it. All gum had to be treated in this way if it was to fetch a good price. Sieves were used to separate smaller gum nuggets from surrounding soil and debris.

Some refer to the resin as kauri amber. Amber is a generic term for fossil resins aged over four million years exuded by extinct conifers. Resin less than four million years old, which has begun to harden but does not yet have the physical prop­erties of amber, is called copal, and “kauri copal” is a term favoured by Northern Hemisphere varnish mak­ers of the past.

Thereby hangs the tale, much of it apocryphal, part nostalgia, frequently tragic, of kauri gum and Northland’s continuing tendency to boom and bust. For the purposes of the tale, the vernacular “kauri gum” is at least expedient.

Before the arrival of Homo sapiens, and thus before the products of nature were seen as raw material, put there exclusively for our picking, kauri forest covered much of Aotearoa.

Kauri gum has been found in lig­nite seams at Gore in Southland and associated with coal at Roxburgh in Central Otago. Kauri will grow, and do grow if tended, in Dunedin and Christchurch, well south of the more recent cut-off line for naturally oc­curring kauri at the 38th parallel (Kawhia to Opotiki).

But by the time the voyaging for­bears of the Maori arrived, kauri for­est covered only pockets, and larger tracts of the area between Kawhia in the south and Kaitaia in the north. Apart from an isolated sprinkling in the vicinity of Spirits Bay in the far north, the peninsular area between Kaitaia and Cape Reinga was de­nuded.

What caused the disappearance of the countrywide covering, and espe­cially the more recent and mysteri­ous absence of living trees on the rich gumfields of the Aupouri Peninsula, is a matter of much and varied specu­lation.

Theories range from the scientifi­cally respectable ice ages, volcanic activity, tidal waves, continental side-step, soil deprivation and fires, through the legendary upheavals brought about by the struggle be­tween the Maori god Tane and his parents, to fanciful giant aliens with chainsaws.

No two pieces of gum are alike. Gum buyers recognised at least 50 different grades, going from almost colourless and clear “dial” gum to almost black swamp gum, along with grades for young “candle” gum, oxidised “sugar” gum and many other varieties. This piece has a pronounced reddish tinge, perhaps the result of heat through a slowburning bushfire.

The Aupouri, called by Cook “the desart (sic) shore” because of its then rolling sandhills, bears underground evidence of having been clothed sev­eral times with successive layers of kauri forest. The most recent layer, carbon-dated as 3000 years old, lies buried in a jumble of peat swamp, pumice and sandstone, and its place­ment raises more questions than it answers. Most of the gum is to be found in swamps, yet living kauri do not like wet feet. At low tide, ancient logs stick up out of the channel of the Houhora Harbour, while at the head of the harbour layers of pipi shells are found 40 feet up, on Mt Camel, and 60 feet down, in boreholes at sea level.

In places the logs lie with their stumps and roots in the ground and their huge trunks lying neatly east to west. To add to the mystery, there are other places where the stumps and branches are buried in logical pat­terns, but there is no sign of the trunks.

Sitting in the Wagener family’s museum at Houhora, looking at gum and listening to speculative talk of the land and its ups and downs, one feels a sense of imminent eruption or plunge, as if the land were an eleva­tor, and some cosmic lift operator might suddenly press the “down” button and head for the boiling core.

Roy Wagener reckons there are now more theories than logs.

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From the earliest Maori occu­pation until the first pakeha arrived, kauri gum could be found lying on the ground in Northland.

At the beginning of pakeha con­tact several Maori uses of kauri gum were recorded. Gum straight from the tree was boiled until soft, puha juice added, and the gum was then chewed communally. Contemporary Maori medicinal use of the chewed gum as a treatment for vomiting, diarrhoea and digestive upsets would suggest that early observers were watching an event which was more pharmaco­logical than social—a conclusion strengthened by the fact that other copals are used medicinally in the tropics.

Maori also used the resin, which burns bright and hot, as a fire lighter. Later, pakeha exploited this use in the making of matches, and still to­day, in households around Northland, a handful of glittering dust from the bottom of the gum bucket does wonders for wet wood in the winter.

Maori burnt the gum as torches, both for lighting the way and attract­ing fish, and used it in the kumara plantations as an insect repellent. The pigment used in Maori facial tattoos was sometimes obtained from kauri gum, either by burning the gum and mixing the pounded soot with oil, or by burning the gum and col­lecting the pigment on branches or leaves which had been smeared with animal fat and suspended in the smoke.

The first pakeha sighting of gum led to one of those endearing and enduring cases of mistaken identity. Captain James Cook is said to have picked up a handful of gum from under mangroves at Mercury Bay in 1769. He concluded that the gum came from the mangroves, and the plant was duly named Avicennia resinifera, after the Arab physician and astronomer Avicenna, and the resin.

A fully kitted-out gumdigger with spear, spade and axe on his shoulder, a bucket for sluicing, a billy for the midday brew and a haversack or “pikau” for carrying the day’s haul. The small flour bag in the digger’s hand was kept handy, usually attached to the belt, for storing small pieces of gum encountered while digging for larger specimens.

Laing and Blackwell’s Plants of New Zealand quotes an even more elaborate embroidery of the original mistake: the mangrove “exudes a kind of green aromatic resin which furnishes a miserable food to the bar­barous natives of New Zealand.” It was not until 1819 that the first re­corded pakeha identification of the resin as a product of the kauri was made—by Samuel Marsden.

When the rush for this northern gold started, the diggers had in mind less utilitarian uses for the gum than did the Maori: it would be used to beautify and improve the lives of peo­ple in far-off countries as linoleum, varnish, paint and polishes.

In providing the gum for these pur­poses, the diggers would, they imag­ined, make their fortune. Thousands of hopefuls from all over the world rushed towards the treasure… but most would merely eke out a living in the miserable conditions.

And in so doing they would leave behind a devastated countryside, one that was turned over and burnt over.

Hand in hand with the timber mill­ers, they would strip the landscape of its forest cover, leaving behind the legacy of the bleak, denuded lands of today’s Northland. But another part of the legacy of the diggers would be a New Zealand culture made richer by the influx, a culture from which some of our major industries would spring.

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In 1815 a cargo of gum from the Bay of Islands was exported to Sydney and put up for auction. It attracted little interest.

Charles Darwin, on being shown a kauri at Waimate North, noted in his journal of 1835 that “a quantity of resin oozes from the bark which is sold at a penny a pound to the Ameri­cans but its use is kept a secret.”

A Whangarei newspaper report claims that in 1836 Captain James Clendon, Magistrate and Collector of Customs at Rawene on the Hokianga, sent a trial shipment of 20 tons of gum to London. The cargo was pro­nounced worthless and dumped into the Thames. Some time later, so the story goes, a small boy playing on the banks found a piece and took it home, talking about “a stone that floats”. His father, who was in the varnish trade, had the gum analysed and traced back to the ship, thus initiat­ing a 100-year export industry.

Eight years after Clendon’s ship­ment, John Logan Campbell and his partner William Brown disposed of a speculative shipment of gum from Hokianga to the fire kindler and ma­rine glue trades in England.

Gilbert Mair, a Whangarei pioneer, had a thriving gum-for-blankets deal going with the Maori at Kaitaia by 1845—red blankets earned more than twice as much gum as grey.

Sod and sacking huts were typical gumdigger shelters right Lip until the 1930s. Here one digger sell’s sacks for roof and walls while another scrapes gum. Note the billies hanging on a gum spear over an open fireplace.

The Mair trade had also grown from children’s happy knack of col­lecting treasure. The Mair offspring’s find of gum in the 1830s was left on the mantelpiece and noticed there by a visiting whaler, who offered fourpence a pound for gum to use in varnish manufacture. William Brown reported in 1845 that large quantities had been exported to America, where it was made into copal varnish, and predicted a great future for the trade.

At the peak of the industry there were 20,000 gumdiggers in the north. First on the fields were the Northland Maori, joined later by Maori from the King Country, Waikato, and the Bay of Plenty. By the 1880s, word was out around the world, and diggers flooded in from Yugoslavia, China, England, France, Malaya and Ger­many. British diggers and runaway soldiers from the New Zealand land wars mingled with fez-wearing Bosnian Muslims, who were mis­taken for Turks, and Finns who were mistaken for Russians.

But the ethnic group which had the greatest presence was the Yugo-slavs. Known then as Austrians, later as Dalmatians, they were a collection of distinct and separate peoples from the states of Dalmatia, Macedonia, Bosnia-Hercegovina, Croatia, Slov­enia, Serbia, and Montenegro.

They emigrated from their home­lands, mainly Dalmatia, in response to problems at home caused by for­eign domination and exploitation. Population growth, peasant farming on ever-decreasing land holdings, phylloxera in the grapes and political unrest after the Austrian annexation of Dalmatia in 1815 made emigration of sons to greener pastures a means of survival for many families.

The first arrivals had no intention of staying. Their aim was to work hard, make as much money as possible and return home. Some, in fact, made the long return journey three or four times.

When they arrived in New Zea­land they were technically Austrian, but ethnically and sympathetically otherwise. And, like the Chinese on the goldfields, they were persecuted. The Yugoslavs’ great industry, co-op­eration and ingenuity made them for­midable workers on the gumfields. Their success led to resentment among other diggers and, fuelled by fluctuations in gum prices and tradi­tional British suspicion of foreign tongues, resulted in their scapegoating.

In 1898 anti-Dalmatian feeling cul­minated in a commission of enquiry. The commission set aside reserves of Crown Land for British, Maori, and naturalised New Zealanders to dig for an annual fee of five shillings. Aliens had to dig ground already picked over by the others, and had to pay £1 per year for their licences.

Racial prejudices are not so easily assuaged, and still the persecution persisted. When World War One broke out, broiling suspicions erupted into accusations that the “Austrians” were enemy aliens. The finding by the Aliens Commission of 1916 that Yugoslavs were loyal, law-abiding citizens was publicly de­rided.

section through a piece of gum in which a number of separate resin flows have covered each other.

Nevertheless, stories of Yugoslav success are legion. Their legacy in­cludes the stone walls of the volcanic mid-north and the New Zealand wine industry. That the Yugoslavs have survived, prospered, and main­tained their cultural heritage throughout Northland, in the face of this barrage of slings and arrows, seems miraculous.

There is a commonly held belief that gumdiggers were a shiftless, un­skilled and lawless lot with no vision or prospects, whose children’s chil­dren live on in Northland in dole‑funded limbo because no subsequent industry, excepting the brief Marsden Point boom, arose to employ them. In fact, gumdiggers worked inhumanly hard, often in foul circumstances, their only crime a kind of blithe hope. Most were single men; most lived in small huts made of timber, sod, and corrugated iron. Some lived in shan­ties made from grain sacks.

At day’s beginning they would walk several kilometres to the patch they were digging. Often they worked in water as they searched the wetlands and peatlands, working down through the rich deposits of sediment, soil, and decaying vegeta­ble matter which had been carried down with the gum from surround­ing hills. While several men dug holes, another operated a primitive hand-pump made of makeshift pip­ing—sometimes jam tins soldered together. Most of the holes were one to four metres deep, but groups of diggers sometimes worked 12 metres underground.

At night and on wet days they would scrape the gum, a necessary prerequisite for sale—paler grades were worth more than darker gum. On Sunday the diggers would bake bread, wash their clothes and mend their equipment. In their spare time they would play cards, play musical instruments and devise ingenious whimsies from the gum, carving it into Bibles and hearts and crucifixes; into bottles and beads and cigarette holders.

At first, kauri gum was collected from the surface of the ground. In hilly country a digger could often tell from the contours of the land where a kauri tree had fallen, and by finding where the head of the tree was, could usually find gum. As the price rose, surface gum rapidly disappeared and the gum-seeker was forced to look underground.

Early diggers used spades and sometimes spears to find the gum. The Skelton gum spade, with its ash handle and tapered, forged blade is said to be the spade that dug the foundations of Northland. Designed especially for the gumfields, it re­mained in production until 1971, when hand-forging and die-making were replaced by assembly line pro­duction. For extra strength, the spade was strapped and riveted front, back, and sides, and it featured foot treads.

In wet places a long spear with a handle was used to locate the gum. Dorall Blucher, a gumdigger who worked in the Ahipara area in the 1940s, says that gum teams usually had a specialist spearer who could tell by the sound the spear made whether it had struck gum.

Brian Wagener describes the ad­aptation known as a “button” or “joker”, which made spearing for gum easier.

“It was hard to put in a spear. The story I was told is that someone talk­ing to his mate had a spear in his hand and prodded through an eyelet off a boot by mistake. He pushed it into the ground to try to get it off and found that the spear was easier to get into the ground with it on.

“After that they made them out of four turns of wire. There was quite an art in twisting the wire. If the joker scratched past a piece of gum, traces were left on the side, so you could tell what sort it was.”

In wet places a gum hook—like a blunt spear with an inch and a half right angle at the bottom—was also used. This sometimes obviated the necessity to dig a hole, and could be used by experts to manoeuvre swamp-buried logs out of the way.

A cut-off kerosene tin with added handle was the universal gum con­tainer. When filled, the gum would be emptied into a sack and carried back to the shanty at the end of the day. There, accumulations of dirt and the crusty exterior of the gum had to be cleaned off with a sharp knife.

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While some climbed for gum, others dredged for it and even dived for it, in lakes where kauri logs had lain for millen­nia. A few tried chemistry to per­suade the swamps to give up their wealth. Various methods and sol­vents were used, with brief flickerings of success and rave re­views, to extract oil, resins and waxes from kauri gum, timber and peat. The most recent of these ventures was Kaurex.

In 1985 the Kaurex Corporation Ltd aimed to establish a commercial venture to extract resins and waxes from peat on 1400 hectares of Crown swamp at Kaimaumau, north of Awanui, by means of organic sol­vents. These compounds would then be purified and sold, for use in such diverse applications as carbon pa­pers, printing inks, polishes, paper coatings, high precision casting waxes, leather finishes, wax coatings for food packaging and lipstick that wouldn’t melt in the sun.

Kaurex was confident of success. Chemical analysis showed Kaimau­mau peat to be between 5 and 10 per cent soluble matter. Market research indicated strong demand for the products they would recover, espe­cially the waxes. The extraction tech­nology had already been successful in obtaining waxes from South Island lignite deposits, and pilot extractions in the laboratory showed that the peat would indeed deliver its riches. In­vestors were found, equipment as­sembled and the plant was built.

Whangarei sharebroker Frank Newman described the market at the time as “so buoyant you could float the Titanic”.

Engine-driven tub washers, like this one from the mid-1910s, were used to speed up the process of separating gum from soil.The Kaurex resin and wax extraction plant at Kaimaumau shimmers as solvent is burned off during its decommissioning in 1989. The plant was the most recent in a long line of attempts to extract kauri gum chips and dust from Northland’s peat swamps.

On February 11, 1985, the then Archbishop of New Zealand con­ducted a service in a large corrugated iron shed to pray for successful min­ing.

By March 1987 the final products were reported as being weeks away, but no product ever came out of the plant. By February 1988 the company was in receivership, and in 1989 the dismantled plant was auctioned. To­day, little can be seen of the spectacu­lar stainless steel structure which once stood out on the coastal skyline. The whole site is under a metre of scrub, and the gum remains locked up in the ground.

What happened?

The verdict from locals is that the project was “doomed from the start”, but the actual problems were techni­cal, climatic and financial.

The process required the peat to be dried. Colin Putt, chemical engineer on site says: “At one stage I was a salt maker. I learned about solar drying. You can’t do it in a humid climate like Kaimaumau.”

Insects of all shapes and sizes, and even small rodents, were frequently entombed by the glutinous kauri resin as it dripped down the tree. If the resin is old enough, these inclusions can be of great scientific interest recently, a study was made of the cells of a 40 million-year-old fly trapped in amber. Even this centipede’s powers of locomotion were not enough to save it from a sticky end.

Spent peat, from which solvents had already recovered the resin and wax, was to have fuelled steam boil­ers. However, a problem in boiler de­sign made this impossible, and the necessity to use coal instead caused cost overruns.

Sand in the peat caused abrasion to the pipes and equipment, and the main extractor itself kept clogging up. When this happened, the resin set solid in the pipes and had to be chipped off. Furthermore, the recov­ery of the solvent was less effective than had been predicted. Kaurex had chosen the relatively expensive butyl acetate in order to extract higher qual­ity waxes, and soon the company was in financial trouble.

As it happened, this was the time of the sharemarket crash, and refi­nancing proved impossible. Putty “The valuable resources of Kaimaumau are still there. Kaurex had a good source of raw material, good process, good product and good markets, but they bit off more than they could chew.”

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No two pieces of gum are the same gum bleeds from all parts of the tree, and the roots, trunk, knots, branches and cones all produce resin of different quality.

Rei Hamon, an artist who collects gum for his art gallery and museum in Thames, explains: “There’s a dif­ference in the gums which come from trees which are dying, trees that have grown on storm-swept rocky ridges, trees that have flourished in the swamps of Northland, and trees that have grown on the clay- and mineral-impregnated ridges of the Coro­mandel Peninsula.

“All of these factors add to the colours or shades of the gum, which range from nearly blacks to a clarity not unlike glass.

“The gum that bleeds from the northern side of the tree will receive the greatest amount of direct heat from the sun and will usually pro­duce gum of the most beautiful shades of gold.

“If this gum drips off the roots on to the rocks it then turns a deeper gold because of the greater heat gen­erated by the sun on the stone.

“If a large piece of gum is buried, say 40 centimetres under the ground, and a large kauri has caught fire above it, steady sustained heat that has gone down through the ground will give different beautiful shades of wine.”The longer the fire’s heat lasts, the darker the gum will be.”

Hamon tells of old gumdiggers who would put green gum in paper moulds and bury it under the cook­ing fire in their camps. “They knew just when to take it out, depending on what shade they wanted. When it was cold they would then carve it into beautiful things and polish it.”

Carved gum bust, said to be of Hokianga chief Tamati Waka Nene. was one of a series carved in the early 1900s. Gum heads were popular curios, but they were usually made by pouring melted gum into a mould, and were Jess attractive than the carved variety.

When it came to grading gum for commercial purposes, colour was only one of the criteria. Size, hard­ness and purity were also taken into consideration. In order of decreasing size, the pieces of gum were known as nuggets, nubs, peas, chips, and dust. Range gum, which came from the hills, was the hardest; the softest was chalky gum from the swamps. White range gum was the most valued, then white swamp gum. Black gums, also from the swamps, and bush gum, from living trees, were two of the lower grades. At one time as many as 50 sub-grades were recognised.

By the 1940s, exports of kauri gum had declined to less than 300 tons annually. The trade was all but over. The decline and fall, blamed sometimes on increasing scarcity of gum or, optimistically, on the lack of a universal grading system, was ultimately caused by the development of competitive synthetics. Alkydbased varnishes, with their ease of application and fast drying times, quickly superseded copal varnishes, and the advent of vinyl sounded the death knell for linoleum.

But with the virtual passing of the gum industry, there remained the vexed question of what could be done to put right some of the damage the landscape had suffered at the hands of diggers. One of the “solutions”, while seeming like a good idea at the time, proved to be a terri­ble blunder. It was the introduction of gorse.

The Kauri Gum Commission Re­port of 1898 advised setting aside an experimental farm for gorse pasturing, with a view to reclaiming gum lands, saying that land which could not feed one sheep to the acre had been made to carry and fatten five or six sheep to the acre when planted with gorse. Northland is now glutted with the pest, and lacks the economic strength to get rid of it.

Patu (club) shaped by Gordon Fergusson, Matakohe, shows ripples of different coloured gum, indicating a number of separate resin flows when the lump was being formed.

Another outcome of the passing of the kauri gum industry was a tung oil venture. Touted as a replacement commodity for declining kauri gum, tung oil is obtained from the seeds of Aleurites fordii and A. montana, na­tives of China.

In 1933 the Journal of the New Zealand Institute of Horticulture re­ported 100,000 trees planted and a rosy future in exports of tung oil for use in paint, lino and waterproofing and insulating materials. The trees failed to thrive on a high water table, winds blew out the tops, synthetics arrived… and rumours still abound in the north about the authenticity of the venture.

All that remains are a few standing trees in the far north, rows of stumps in the Mangakahia Valley and a won­derful story of not one, but two Rolls-Royces buried in the sand on Ninety Mile Beach by a tung oil entrepre­neur.

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There is no doubt that kauri gum subsidised the development of Northland’s farms and trans­port systems. Many of the original farmers came first to dig gum, then financed their land purchases with the profits, underwrote subsequent farm development by devoting a por­tion of the working week to gumdigging, and capitalised on the land clearance to make fine farms. Some negotiated gum-for-land-clear­ing deals with itinerant diggers.

But the kauri gum industry would appear to have done more for the bank balances of Auckland dealers, government coffers, and the North­ern Hemisphere manufacturers who gained the added value in processing the raw material, than it did for Northland.

Northland bought survival, re­ceived a pittance and lost a resource. Ever since, it’s been seen as the back of beyond. A nice place for a holiday or a sketching tour, but not, unless you’re a fairly masochistic dairy farmer or an employee of the Depart­ment of Social Welfare (on the right side of the desk), a serious living and working environment.

Elaborately-built lighthouse is one of a number of impressive gum structures in the Matakohe Kauri Museum. It is thought to have been made around 1905.

In the past, for the promising sons of Auckland to go north was a dis­grace. Northlanders were gumdig­gers, Maori and “Dallies”, and none of these epithets was a compliment. Even today, the view of the north, which is consistently left off the top of maps, out of weather forecasts and arts diaries and omitted from all but the most philanthropic and deter­mined of fringe cultural tours, is of a balmy haven for the unemployed, radical Maori and marijuana farmers.

Yet, going among the gumdiggers, seeing their strange land, feeling the dancing ghosts in places where only a pile of tin might remain as witness of the disappearance of whole towns, and hearing their stories, it’s difficult not to feel a little like a gumdigger yourself—prospecting for the beauti­ful shiny buried pieces of their lives.

On the high Ahipara gumfields plateau above Shipwreck Cove, where the grandson of the “last dig­ger” lives among the bent-backed scrub with no electricity, a tribe of dogs priming for the hunt and his grandfather’s dreams for company, my fingers wanted to dig into the podzolised wasteland.

For a moment in the wilderness, the vision of treasure from the earth seemed possible.

Vanrish, lino and false teeth

It is estimated that half a million tons of kauri gum left New Zealand shores for North America and England. The two main uses of the resin were in varnishes (both oil-based and spirit-based) and linoleum.

Before the advent of kauri gum, varnish makers used a variety of resins, and sometimes amber, to produce their lacquers. The usual method was to melt the resin in an iron or copper vessel, and then to stir in heated oil, usually linseed. It was a skilled profession, with polish­ers boasting secret formulae and arcane techniques. It was also dangerous. Most resins had high melting points, and the process of mixing them with flammable oils at elevated temperatures could lead to spectacular explo­sions.

Once made, these varnishes were difficult to apply, took a long time to dry and gradually darkened with age. While kauri gum could not overcome prob­lems of application and drying time, it had two distinct advan­tages over other varnish bases: it held its colour better and, because of its lower melting point, was much easier and safer to handle during manufacture.

By the turn of this century, kauri gum had established itself as the premier varnish resin and, as well as being used for protect­ing the elaborately painted and lined interiors of horse-drawn carriages (it is said that kauri gum varnish is still specified for the revarnishing of the Queen’s coach), was being brushed on to boats, houses, furniture and even oil paintings. It was also combined with pigments to make enamel paints, and, in later decades, a variation made with a higher gum-to-oil ratio was used to coat the armature windings of electric motors.

While the trade houses of Britain, Europe and North America were turning out thousands of gallons of kauri gum varnish, some varnish makers were combining the gum with shellac and other copals to produce a durable French polish which gained popularity as a coating for higher quality furniture. It was found that the addition of kauri gum to a shellac polish gave it better water resistance and greater elasticity, but made it more difficult to apply. By the early 1900s much of the furniture output of the Northern Hemi­sphere was being coated with New Zealand kauri gum var­nishes and polishes.

Today, synthetics have supplanted natural resins, and kauri gum varnishes are only used in specialised fields such as the polishing of stringed instruments, or by furniture restorers seeking to match the original polishes on antique woodwork. For long-term applications, the resin is nor­mally mixed with other compo­nents; kauri gum on its own tends to develop a “crazed” surface with age.

Hamilton violinmaker Ian Sweetman uses kauri gum in his varnishes—along with such romantic-sounding ingredients as sandarac, gum mastic and oil of lavender spike. “Kauri gum gives the varnish added toughness,” he says, “and because of its good refractive index it makes the wood shimmer when the instru­ment is moved.”

Only the highest grades of gum (the palest varieties) were suit­able for varnish work, but that left a huge amount of poorer quality gum and gum “chips”—fragments of gum which, in earlier days, had been scraped off the bigger lumps and forgotten. Then, along came the linoleum industry, and gumdiggers struck the jackpot for a second time.

Developed in 1863 by Frederick Walton, lino was made from linoxyn (obtained from the oxidation of linseed oil) melted with resins and allowed to cool.

The product of the melt was mixed warm with cork and pigments and rolled into sheets. The result was a tough, durable floor covering—one which, until the introduction of vinyls, probably graced most homes in New Zealand.

Kauri gum was used initially because it was the cheapest resin available, but later, resins from the Congo were cheaper—hence congoleum.

Other lesser known uses for kauri gum include impression moulds for false teeth (still used today in India) and as a binding agent in phonograph records.

Kauri gum curios

When they weren’t scraping it for a living, some diggers spent their spare hours at night carving gum and making curios under candle and kerosene lantern light. Some of the more extraordinary whimsies that remain, such as gum “hair” and magnifying glasses, are now part of New Zealand’s folk art.

Like amber, gum sometimes harbours inclusions, such as plant material, insects and small animals, which are preserved forever by the gum’s embalming qualities. These entombed objects can be of great scientific interest, especially if the resin is old enough for the inclusion to be a creature now extinct.

By carefully melting gum and pouring it into moulds, diggers learned to make their own inclusions, using everything from photographs of loved ones to lizards and mice.

Other diggers carved objects like cigarette holders, bottles, beads and Bibles, and one digger, over a period of ten years, created a model of a cathedral from 600 separate pieces. It now resides in the Matakohe Kauri Museum, along with the largest collection of gum and gum curios in the country.

One of the oddest uses was the making of gum “hair” which resembled flaxen tresses—bright, gold, and fine. In his booklet Kauri Gum, The Simple Art of Enhancing Its Beauty, Thames artist Rei Hamon gives the following instructions on how to make the “hair” (slightly abridged):

“First you need an electric hotplate for your heat source. Cover it with a smooth steel plate, then get something else very smooth, about three feet long and one foot wide—I use a piece of thick lino— and place it next to the hotplate. This is for laying the hair on as you make it. Use a large enough piece of gum to hold easily in one hand. Press the gum firmly onto the heated steel plate for a few seconds until it starts to melt and then lift it off slowly, until the fine strands formed start to break. Touch the strands near the bottom with your free hand, and then float them on to the catch­ing surface. Repeat the process until you have enough hair to plait or wind into a bun. You need to work quickly, then arrange it as you want and put it where you intend to keep it. Once it’s cold it is very brittle. Don’t touch it again.”

Kauri gum is still used as a jewellery medium. Carver Paul Seville of Whangarei makes earrings, pendants and sculp­tures, often presenting them in swamp kauri cases. Seville claims to be one of the few contemporary craftspeople who carves the gum. He uses band-saws for cutting, and drills under water for shaping. He coats the gum with a two-pot marine resin to prevent the scratching which, in the past, has militated against a wider use of kauri gum in the jewellery trade.

In spite of its fragility, Seville sees a place for gum: “If you’ve got a piece that’s 5000 years old, you’ve got to treat it with re­spect—you’re not just going to chuck it on the dressing table.”

Land of the lost

The gumfields of thenorth, with their raupo swamps, endless dugover terrain and dubious social codes, were generally held in poor regard by townsfolk. To outsiders it must have seemed a forlorn enterprise—turning the whole visible earth upside down with a spade for hardened resin worth only a fraction by weight of the gold harvested downcountry half a century earlier.

Yet the attention of the era’s two best novelists, Jane Mander and William Satchell, has preserved something of the appeal, and the dangers, of life on the fields before the First World War—a core of observed fact polished by literary inven­tion.

Above all, the fields were outlands, lawless marches that bred violence or offered sanctu­ary, depending on your point of view. “The north was not respectable,” wrote Jane Mander in Allen Adair (1925). “It was the land of lost men. It was peopled with nomads and wasters. And it was ‘the roadless north’, the ‘barbaric north’, where the Maoris still might war upon you in the night. It had no railway beyond Helensville. The Southerner curled his lip at it.”

Five years earlier, in The Story of a New Zealand River, she had been even more blunt: “The shades of suicide and murder have always stalked abroad upon the gumlands. Whisky and loneliness have brought many a man to the jump into a swamp, or to a shot that no one heard, or to the rarer use of a razor, while the poach­ing of claims put the brand of Cain upon most of those who killed under the open sky”.

At least, that was the pros­pect as seen from city villas. Auckland magistrates, it has been claimed, would give offenders a choice-14 days in Mount Eden jail, or despatch to the gumdiggings.

In The Land of the Lost (1902) William Satchell describes what would have greeted a convict’s gaze: “In every direction the field stretches itself out to the horizon….Throughout the vast circle hardly a spot can be found which shows no trace of the digger’s spade. Yet so invincible is the manuka…that despite the constant interference to which it is subjected, it covers the field….Once or twice a figure bearing an empty, or partially empty sack on its back, a spade across its shoulder, and a thin spear, shining like a splinter of glass in its hand, came into an open space and prodded the ground here and there. This was a digger spearing for gum. At other times a man might be observed throwing out the soil with his spade; but no figure remained in view for longer than a few minutes at a time”.

The fields were populated by rebels, drifters, remittance men, unemployed mechanics and clerks—underdogs of every description who found amid the physical desolation the freedom to forget the past, at least for a time, and live out their rough lives as equals. The legend arose, says Jane Mander, of dukes’ sons and the sons of belted earls in the gumlands; there was uncer­tainty about everyone a person met. Yet it was no place, at least in the days before trenching and contract work, for the gregarious. It was a vocation for loners—the industry gained nothing from cooperation. Nor did it appeal to the adventurous. The only adventure, as she wryly ob­serves, was the exacting one of living with your own thoughts.

On depressing wet days there was always the diversion of covering draughty cracks in a shanty’s walls using flour paste and cut-outs from hoarded illustrated papers. Or the oner­ous job of scraping gum ready for sale at the local store.

William Satchell describes a typical whare: “The hut was constructed of rushes with a low sliding door of wood. Around it a small piece of land was en­closed in a stake fence, and in the centre of this was a red rose bush in full flower….The blan­kets were folded, as is usual, to prevent them being blown by the bluebottle fly”.

It is the record of a meagre attempt at domesticity in a landscape of social transition and physical transformation. Behind the diggers’ spades crept the farms. Closing on the gumlands and the social mobil­ity and freedoms they fostered were the constraints of organised and regulated twentieth century life.

Lines from a poem Satchell published in 1900, Song of the Gumfield, survive like an insect trapped in amber—a melancholy reminder of a past life beyond reviving. A life at once besieged and resourceful:

“In the slighted blighted North, where the giant kauris grow, And the earth is bare and barren where the bush-bee used to hum, Where the luck we’ve followed’s failing, and our friends are out of hailing, And it’s getting narrow sailing bye the rocks of Kingdom Come. There’s a way of fighting woe, squaring store bills as you go, In the trade of digging gum….

“When the night is growing thicker and the bottled candles flicker. And the damned mosquitoes bicker in a diabolic hum, There’s a way of ending fret and pulling down a debt.

In the task of scraping gum.”

Whangarei writer Florence Keene sits in Jane Mander's hexagonal study, now in the grounds of the Northland Regional Museum. At the time of their publication in the 1920s, Mander's romantic stories of the North were considered too risque for general consumption, and were kept under the shop counter in plain brown wrappers.

Gums and resins

Kauri gum is not a gum at all. To botanists, true gums are polysaccharides which are produced by plants in response to bacterial infection or physical damage. They are hydrophilic (have an affinity for water), and have been used for centuries as adhesives.

Kauri trees, along with other conifers and some families of flowering plants, exude sub­stances which are hydrophobic (water repellent) and which harden on exposure to air to form glassy solids. They are called resins, and are usually mixtures of chemicals called terpenoids. Both gum and resin differ from sap, the watery solution that carries minerals and nutrients around the plant.

The function of resins seems to be twofold: to repair wounds and to defend the plant from fungi, insects and microorgan­isms which might attack it. Interestingly, the trees which produce large amounts of resin occur mainly in tropical or subtropical regions—the very places where plant-attacking organisms proliferate. This observation points to a defence role for resins, and they certainly seem to work: many of the resin-producers are forest giants which live for hundreds or, in the case of kauri, thousands of years.

Kauri resin is produced in many parts of the tree, and the chemical composition of the resin varies according to its position. Different resins have been identified from the leaf surface, from resin canals inside the leaf and in the bark, from deep in the heartwood and from the roots. The resin which forms the large lumps prized by gumdiggers comes only from the heartwood and the bark resin canals.

Chemically, resins have two components: a small volatile part, primarily monoterpenes and sesquiterpenes (from which turpentine is derived), and a sticky, nonvolatile part which eventually hardens into what we know as “gum”. Rosin, the substance which violinists use on their bows, is made from this part of a pine resin.

When the bark is damaged, the resin emerges as a viscous emulsion of organic molecules and water—a latex. In the air, it hardens. The organic molecules polymerise, forming a skin that blocks off the wound and protects the tree from infection. Why this bleeding process should form large lumps of resin up to 30 or more kilograms in weight is not well understood. It seems that the mechanism which shuts off resin flow doesn’t work in some cases, and resin contin­ues to ooze out of the tree long after the wound has been covered.

On secretion, the resin is a milky colour. As the water evaporates the resin becomes progressively clearer and harder. Eventually, it becomes resistant to environmental change, and can survive intact for millions of years. Older resins which have become hard and tough are called amber, and are regarded as semiprecious, Some Baltic amber has been found in deposits that are 250 million years old.

Traditionally, amber has been thought of as deriving from pines, but recent chemical analysis shows the chemical “fingerprint” to be closer to that of kauri and its tropical allies. In 1989, a study group of the Gemmological Association of New Zealand found that kauri resin is similar to ambers of the Dominican Republic, but differs from Baltic ambers in having a lower succinic and abietic acid content. It is thought that these acids make amber harder, tougher and more durable than even the oldest kauri gum, and this means that the surface is less likely to deteriorate after polish­ing. The surface of polished kauri gum becomes “crazed” with time: a network of fine cracks about a millimetre deep develops over the entire piece as volatile components of the resin continue to evaporate. To get rid of the cracks, the piece must be repolished, although New Zealand gemmologist Spencer Currie, who has researched the properties of amber and kauri gum, reports that by rubbing wheatgerm oil into the surface the cracks can be rendered nearly invisible.

The oldest New Zealand kauri gum, found in coal deposits, is thought to be around 50 million years before the present. Most of the gum collected by the diggers would have been up to a few thousand years old, though swamp gum could be consider­ably older—as much as 40,000 years old, according to recent tests.

Let it shine!

Auckland kauri gum polisher Geoff Fergusson describes the process of converting an opaque lump into a piece of shining gold.

Select a piece of gum that is as smooth as possible, with a thin, hard outer crust.

Examine the piece carefully and choose the best face for polishing, preferably without major fissures or depressions.

Using a very sharp knife, gradually carve off the oxidised surface gum until solid gum is revealed. If this crust extends throughout, you have a piece of “sugar” gum, which is not polishable. If your knife sticks, your piece is too soft to polish.

Shape as desired, keeping the surface as smooth as possible and removing all surface pits. At this stage you need to decide whether you are going to polish the piece all over or leave a backing—a section that is left in its natural state. The second approach often results in a startling internal “landscape” which vastly increases the visual impact of the gum.

Using progressively finer grades of wet & dry emery paper, sand your gum to a silky-smooth, flawless finish, using water to keep the surfaces cool and lubricated as you work.

For final polishing, a number of fine abrasive polishes can be used, such as Brasso, jewellers’ rouge, whiting mixed with olive oil, all applied with a soft cloth.

Give a final buff with a soft cotton or silk cloth, and there you are: gleaming treasure from the dawn of pre-history!